We would like to inform you that, we have changed the name of our kits for TREC and TREC/KREC screening from SCREEN-ID to the new trade-marked name SPOT-it™ as of October 12, 2018. The products are identical and will carry the same product codes as previously. We hope that the change will not cause any confusion or inconveniences.
The SPOT-it™ neonatal screening kit for severe primary immunodeficiency diseases is an all-in-one system for the quantitation of T-cell specific TRECs (T-cell receptor excision circles) and/or B-cell specific KRECs (kappa-deleting recombination excision circles) as well as quality control markers (beta-actin) using commonplace quantitative real-time PCR (qPCR). The SPOT-it™ kit employs regular 3.2mm Guthrie card spots and features a Filter plate concept to rinse samples prior to analysis. The kit includes all necessary reagents pre-arranged in a set of Elution and qPCR plates and requires only two pipetting steps. (Figure 1)

Figure 1

The SPOT-it™ kit includes standards and control card material for absolute quantitation of TREC, KREC and beta-actin copies and enables the user to perform prospective newborn screening based on diagnostic cutoff values. The cutoff values suggested for use with the kit have been optimized to detect the most severe forms of T- and B-cell lymphopenic PID, like SCID and agammaglobulinemia. (Figure 2)

A growing number of investigations suggest, that the SPOT-it™ kit can also be used for detection of other forms of PID, including ADA-deficiency, severe DiGeorge (22q11) syndrome and pronounced Nijmegen-breakage-syndrome.(1-3)

Figure 2

Compatibility & Multiplexing

The SPOT-it™ kit features a standard ANSI/SLAS 96-well format with 84 sample positions per plate (excl. control card material). In a typical mid-scale laboratory setting, up to six qPCR plates can be run per day (~500 samples). Up-scaling is feasible and depends on the availability of additional thermocyclers and qPCR systems.

As the triplex-detection chemistry for TRECs, KRECs and beta-actin markers is independent of each analyte, the user can tailor the required diagnostic output of the SPOT-it™ kit. Some users might limit the screening approach to TRECs-only, while others choose to report both TRECs and KRECs.(4,5)